The United Nations Tuesday released a new assessment of the 1986 Chernobyl nuclear meltdown, saying the worst health consequences for 7,1 million people may be yet to come. "At least 100 times as much radiation was released by this accident as by the two atomic bombs dropped on Hiroshima and Nagasaki combined" at the end of World War 2, said a 32-page booklet titled Chernobyl: A Continuing Catastrophe, released to mark the 14th anniversary of the disaster.